Airtight sheath being adjustable in size for packing

Abstract

An airtight sheath includes a first buffering unit, a second buffering unit, a bottom buffering unit, and a foldable unit. Two terminating sides are formed at opposite sides of the second buffering unit to be heat-sealed to two opposite sides of the first buffering body. A packing space is formed and surrounded by the first, second, and bottom buffering units. The foldable unit includes a bending body, and a plurality of abutting air columns. The bending body is bendable from the second buffering unit so that the foldable unit is foldable into the packing space, where the packing space is capable of being narrowed by the abutting air columns and the first buffering unit. The airtight sheath is capable of fittingly packing an object having a small size as the foldable unit is folded, or an object having a larger size as the foldable unit is unfolded.

What is claimed is: 
     
       1. An airtight sheath being adjustable in size for packing and made of at least two outer films heat-sealed together, the airtight sheath comprising:
 a first buffering unit comprising a plurality of first air columns; 
 a second buffering unit comprising a plurality of second air columns arranged apart from the first air columns, and two terminating sides formed at opposite sides of the second buffering unit, the terminating sides being heat-sealed to two opposite sides of the first buffering body; 
 a bottom buffering unit comprising a plurality of bottom air columns, two opposite sides of the bottom buffering unit integrally respectively connecting the first and second buffering units such that the bottom air columns correspondingly communicating with the first air columns and the second air columns to enable air to flow thereamong, the first, second, and bottom air columns cooperatively surrounding to form a packing space therein; and 
 a foldable unit integrally extending from one side of the second buffering unit opposite to the bottom buffering unit, and comprising a bending body, and a plurality of abutting air columns extending from and communicating with the bending body, the bending body being bendable from the second buffering unit so that the foldable unit is foldable into the packing space, where the packing space is capable of being narrowed by the abutting air columns and the first buffering unit; 
 wherein the foldable unit further comprises a plurality of foot air columns connected to ends of the abutting air columns opposite to the bending body, and the foot air columns are being propped against the first buffering unit and bend toward the abutting air columns when the foldable unit is folded into the packing space. 
 
     
     
       2. The airtight sheath of  claim 1 , wherein each of the abutting air columns has a length shorter than that of each of the second air columns, so that the abutting air columns completely abut onto a side of the second buffering unit in the packing space for enhancing side protection of the airtight sheath. 
     
     
       3. The airtight sheath of  claim 1 , further comprising a suspending layer located in the packing space, one end of the suspending layer is heat-sealed to a top of the first buffering unit, and another end of the suspending layer is heat-sealed to a top of the second buffering unit, and the foot air columns abut onto a bottom of the suspending layer when the foldable unit is folded in the packing space. 
     
     
       4. The airtight sheath of  claim 1 , wherein the foldable unit further comprises two deflated portions formed at opposite end portions of the foldable unit and being flush and terminated with the terminating sides of the second buffering body, and the deflated portions are heat-sealed to be laminated so as to facilitate folding of the foldable unit. 
     
     
       5. The airtight sheath of  claim 1 , wherein any two of the adjacent second air columns are further provided with a narrowing sealing line, which is heat-sealed with the first buffering unit to further narrow the packing space. 
     
     
       6. The airtight sheath of  claim 1 , further comprising a suspending layer located in the packing space, one end of the suspending layer is heat-sealed to a top of the first buffering unit, and another end of the suspending layer is heat-sealed to a top of the second buffering unit, such that the suspending layer forms a U-shaped configuration in cross section where a bottom of the suspending layer is spaced apart from the bottom buffering unit. 
     
     
       7. The airtight sheath of  claim 1 , wherein the two outer films extend upward of the first buffering unit so as to form an air inflation channel located above and along the plurality of first air columns, whereby air is to flow from the air inflation channel to inflate the entire the airtight sheath.